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brain - definition and synonyms


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noun brain pronunciation in British English /breɪn/
Word Forms
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  1. 1
    [countable] the organ inside your head that allows you to think and feel, and controls your body

    The human brain is divided into two halves.

    The illness had affected his brain.

    1. a.
      [only before noun] belonging to or connected with the brain
    2. b.


      [plural] the brain of an animal cooked and eaten as food
      Synonyms and related words
  2. 2
    [countable] [often plural] mental ability or intelligence

    She felt that she could almost see his brain working.

    You have to use your brains in this job.

    have brains/a brain (=be intelligent):

    He’s good-looking, and he’s got brains.

  3. From our crowdsourced Open Dictionary
    have a brain the size of a planet to be extremely clever (originally said of Marvin the paranoid android in The Hitchhiker's Guide to the Galaxy)

    It's James, he has a brain the size of a planet!

    Submitted by James Strangward from United Kingdom on 19/05/2014


to fall over forwards so that your face hits the ground or another surface

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the activity of exploring abandoned buildings and other manmade structures

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